Hoisting-motor.



No. 733,614. PATENTED JULY 14, 1903. A. A. BALL, JB. HOISTING MOTOR.

APPLICATION FILED APR. 16, 1902. NO MODEL. '3 SHEETS-SHEET 1.

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No. 733,614. PATENTED JULY 14. 1903. A. A. BALL, JR. HOISTING MOTOR.

APPLIOATION FILED APR.16, 1902.

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O TLL UNITED STATES Patented July 14, 1903.

PATENT OFFICE.

AUGUSTUS A. BALL, JR., OF LYNN, MASSACHUSETTS, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

HOlSTlNG-MOTOR.

SPECIFICATION forming part of Letters Patent No. 733,614, dated July 14, 1903.

Application filed April 16,1902. Serial No. 103,096. (No model!) To call whom it may concern:

Be it known that I, AUGUSTUS A. BALL, J12, a citizen of the United States, residing at Lynn, in the county of Essex, State of Massachusetts, have invented certain new and useful Improvements in Hoisting Motors, of which the following is a specification.

This invention relates to hoisting apparatus, and its objectis to provide a simple, coin- IO pact, and powerful machine of this class driven by an electric motor and comprising a selfcontained piece of mechanism which can be moved about from place to place whenever wanted. Such a device is of special [5 value in machine-shops, where it can be mounted on an overhead track and used to hoist and convey heavy castings and the like from one point to another, in warehouses for lifting and transporting goods, in plants for handling ore, coal, grain, and the like, in

quarries, dockyards, and, in fact, almostevery place where things have to be lifted and moved about. My invention comprises a screw which is attached to any suitable abutment, such as a rope, bar, beam, or a trolley running on an overhead track, and in such a manner that while it may swing or rotate in any direction it will resist the end pull of the hoist. Concentric with this screw is an electric motor whose armature-shaft is hollow to encircle the screw and carries a nut meshing therewith. As the motor revolves it travels up or down on the screw. To increase its range of lift, the screw may be made tubular and the armature-shaft may carry a second nut meshing with a solid screw-rod sliding in and out of the tubular screw and arranged to be moved upward at the same time that the motor rises and to run downward when the motor lowers itself. This compound screw action gives a range of hoist preferably about double the travel of the motor. An automatic switch cuts out the motor when the hoist reaches the 4 5 limit of its upward or downward movement. In the accompanying drawings, Figure 1 is a longitudinal sectional elevation of my improved electric hoist. Fig. 2 is a similar section of the upper nut when the hoist is at its lowest point. Fig. 3 is a cross-section on the line 3 3, Fig. 1. Fig. 4 is a longitudinal section of the lower nut when the hoist is at its lowest limit. Fig. 5 is a cross-section on the line 5 5, Fig. 1. Fig. 6 is a side elevation of the armature and its shaft, partly broken away. Fig. 7 is a vertical section of the automatic cut-out. Fig. 8 is a cross-section of the same on the line 8 8, Fig. '7, and Fig. 9 is a diagram of the circuits.

From any suitable track, such as an I-beam 6o 1, is suspended a trolley 2, having an eye 3 for receiving the eye or hook 4 of a socket 5, in which is rigidly fastened the upper end of a long tubular screw 6. Concentric with said screw is a casing for an electric motor, having a body 7 with a tubular neck 8 9 at each end. The upper end of the upper neck 8 has secured to it by a coupling-flange 10 a thick annular collar 11, having a sliding fit on the screw and carrying a spline 12, which engages with a longitudinal keyway 13 in said screw. The collar may be locked to the neck by a lug 14, entering a notch in said neck. This'construction enables the casing to slide longitudinally on the screw without rotating thereon. At the lower end of the lower neck is a similar collar 15, and between the two collars is supported the rotatable armature 16 of the motor. The armature has a tubular shaft 17, journaled in bearings 18 at each end of the body 7 and secured at each end to a nut 19 20, between which and the collars 11 15 are ball-bearings 21. The upper nut19 meshes with the tubular screw, so that when the armature-shaft is rotated the motor will travel up or down the screw, according to the direction of rotation.

In order to increase the range of the hoist, a screw-rod 22 is housed in the tubular screw 6 and meshes with the nut 20 on the lower end 9 of the armature-shaft. The rod passes down through the collar 15, which has a spline 23 engaging with a longitudinal keyway 24 in the rod, so that the latter cannot rotate. The lower end of the rod carries'a hook 25 or other 9 5 means for attaching a load The tubular armature-shaft 17 is preferably connected with the nuts 19 20 by means of lengthwise notches in its ends, which fit over radial. lugs 26, projecting inwardly from sock- IO 1 ets in said nuts, into which the ends of the shaft enter.

The field-magnets L7 are housed in the body 7, to the inside of which they are secured. For convenience in assembling-it is preferred to make the body and necks separate and unite them by screw-bolts 28.

To provide for cutting out the motor when the hoist reaches the limit of its upward or downward movement, there is mounted on the upper neck or on the flange 10 a cylinder 10 25), having an insulating bushing 30, through which project two spring-pressed contacts 31 in circuit with the motor. In the cylinder is a plunger 32, adapted to close the circuit by bridging the contacts 31. A spring 33 keeps I 5 the plunger normally in contact with these contacts, but permits it to be forced down to break the circuit whenever the hoist rises so high that a stem 8% on the plunger strikes a stop on the socket 5, as shown in Figs. 1

and 7. Attached to the plunger is a cord 36, fastened to the trolley end, of such length that when the hoist reaches its lower limit of movement the cord pulls taut and lifts the plunger out of contact with the contacts 31,

thereby breaking the circuit and stopping the hoist.

The current can be brought to the motor through a flexible cable connected with a contact-trolley running on a supply-conductor 0 near the track 1, said track serving as the return-conductor. This arrangement is common in telpher systems, and therefore it has not been illustrated. A reversing-switch 37 at some convenient point in the circuit serves to reverse the armature connections in the usual manner. For convenience it may be mounted on the motor-casing and operated by cords 3 In accordance with the provisions of the 40 patent statutes I'have described the princi ple of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof but I desire to have it understood that the apparatus shown is only illustrative and that the invention can be carried out by other means. hat I claim as new, and desire to secure by Letters Patent of the United States, is 1. An electric hoist, comprising a motor having an upright tubular shaft, and a compound system of screws passing through said shaft and operated by said motor.

2. An electric hoist, comprising a motor having an upright tubular shaft, a screw passing through said shaft, a nut on the shaft meshing with the screw, and means for suspending the screw.

An electric hoist, comprising a suspendcd tubular screw, an electric motor having a tubular shaft concentric with said screw, a screw-rod inside of said tubular screw, and nuts on the motor-shaft meshing respectively with the tubular screw and the screw-rod.

4. An electric hoist, comprising a suspended screw having a longitudinal keyway, a motor-casing having a spline engaging with said keyway, a tubular armature-shaft concentric with said screw, and a nut on said shaft meshing with said screw.

5. An electric hoist, comprising a suspended tubular screw having a longitudinal keyway, a screw-rod in said screw provided with a longitudinal keyway, a motorcasing provided with splines engaging said keyways, and a motor-armature carrying nuts meshing with the tubular screw and the screw-rod.

6. An electric hoist, comprising a suspended screw having a longitudinal keyway, a casing consisting of a body with a tubular neck concentric with said screw, a collar secured to the end of said neck, and having a spline entering said keyway, a motor having a tubular shaft concentric with the screw and having a bearing in said neck, and a nut on said shaft meshing with said screw.

7. An electric hoist, comprising a suspended tubular screw having a longitudinal keyway, a screw-rod also having a longitudinal keyway and sliding inside said tubular screw,

a casing consisting of a body with a tubular 9 neck at each end concentric with said screw,

a collar secured to the end of each neck, splines on said collars engaging respectively with the keyways in the screws, a motor having a tubular shaft concentric with said screws, and nuts at the ends of said shaft meshing respectively with the tubular screw and the screw-rod.

S. In an electric hoist, the combination with a suspended screw, of a motor arranged to travel up and down on said screw, and a cutout switch arranged to be automatically operated at each end of the travelof said motor.

9. In an electric hoist,the combination with a suspended screw, of a motor arranged to travel up and down on said screw, and a cutout switch comprising a cylinder, a pair of separated contacts therein, a plunger normally connecting them, and stops adapted to move said plunger when the motor reaches the end of its travel.

10. In an electric hoist, the combination with a suspended screw, of a motor arranged to travel up and down on said screw, and a cut out switch comprising a cylinder having an insulating bushing, a pair of contacts projecting into the cylinder, a spring supported plunger normally connecting said contacts, a stop above and in line with the stem of said plunger, and a cord attached to said plunger and to a point fixed with relation to said screw.

In witness whereof I have hereunto set my hand this 12th day of April, 1902.

AUGUSTUS A. BALL, .IR.

Vitncsscs:

DUGALD McK. I\'ICKILLOP, ALEX F. MACDONALD. 

